Unsaturated diesters of hydrazodicarbonic acid and polymers thereof



pl nted-Jai 29, 1952 2,533 931;

, UNITED STATES PATENT OFF-ICE I 2,583,980 I UNSATURATED DIESTERS OF HYDRAZODI- CARBONIC ACID AND POLYMER S THEREOF Lynwood N. Whitehill, Berkeley, cent, and wiiliam M. McLamoi-e, Cambridge, Mala, assignors'to Shell Development Company, San Franoisco, CaliL, a corporation of Delaware No Drawing. Application January 22, 1948, Serial N0. 642,746

10 Claims. (01. zoo-17.5)

The compounds are unsaturated dlesters of by drazodicarbonic acid. Hydrazodicarbonic acid robuten-z-ol-l, or other halogen substituted alcohols. When the alcohols do not exist as such in the free state, e. g. vinyl alcohol, and it is desired to use a chloroformate having the chlohas the formula is roi'ormic radical linked directly to an olefinic H H 0 carbon atom, such chloroformates can be Propared according to the methods now described in U. s. Patent No. 2,377,085 which is suitable h esters are comp wh n h hydrogen for obtaining reactants such as vinyl, propenyl, atoms of both carboxyl groups oi! the acid have isopropenyl, isocrotyl, l-pentyl-l, l-octenyl-i, been replaced by the radical of a monohydric l-dodecenyl-l, 2-hexenyl-2, 3-tetradecenyl-4, alcohol 01' 2 to 18 carbon atoms which contains l-phenyl-Z-propenyl-l, 3 naphthyl-2-butenyl-2 an oleflnic linkage therein such as is the case and like chloroformates I with vinyl, allyl, cinnamyl, and oleyl radicals, for The reaction of the hydrazine with the unexample. These compounds i'orm polymers with saturated chloroi'ormate is assisted by having a y useful Properties y addition pclymerizabasic substance present during the reaction tion through the olefinic groups contained therewhich will combine with the hydrochloric acid in. A particularly suitable group of compounds liberated by the reaction such as organic bases of the invention with excellent polymerization like pyridine, dimethylaniline and quaternary properties are the N,N' dicarboalkenyloxy hyammonium bases such as trimethyl phenylamdrazines having the alkenyloxy groups of 2 to 18 monium hydroxide, or inorganic bases such as bon atoms w th an olefinic bond attached to hydroxides, carbonates or bioarbonates oi alkali the Second carbon atem from the ygen atom or alkaline earth metals like sodium, potassium, therein. This subgroup has the olefinic double calcium, barium, strontium or magnesium. The 7 bond in the alkenyl radicals in the same strucalkaline agent may be in solution or maybe distural position as it is present in vinyl orallyl persed in the reaction mixture as a finely divided r c l A r preferred subgroup are the solid. Diluents or solvents are convenient to car alk nyl y hydra in s havin alhave present in the reaction mixture and tor this kenyloxy groups of 3 to 10 carbon atoms and an purpose water, benzene, carbon tetrachloride or olefinic linkage between the second and third to dioxane may be used. carbon atoms from the O y n m therein. In effecting the reaction the hydrazine is h er n ain llylype r ls, of which placed in the reaction vessel and the unsaturated allyl, methallyl, crotyl and methyl vinyl carchloroformate along with basic agent are seD- binyl are typical. The most preferred comarately added gradually and simultaneously over Pounds of the invention are three lower mema period of time. Ordinarily atmospheric tembers of the class, namely, N,N' dicarbovinyloxy peratures of 15 to 30 C. are .usually suitable for hydrazine, N. rboallyloxy hydrazine and use in obtaining the desired reaction. In some N' c b l y hydrazine. cases it may be desirable to apply refrigeration The compounds are prepared by reacting the in order to cool the reaction mixture during the appropriate unsaturated chlorotormate, such as 4 reaction, and in some cases higher temperatures. allyl chloroformate or vinyl chloroformate, with e. g. 50 to 150 C. give better results. After comhydrazine. The chloroformates are prepared .by pleting the addition of the unsaturated chlorothe now known fashion of reacting the unsatuformate to the reaction mixture, it is ordinarily rated alcohol with phosgene. In this manner, preferred to heat the mixture at say boiling temchloroformates can be prepared irom such alpe'rature so as to assure completion of the reaccohols as allyl, methallyl, crotyl, ethallyl, tiglyl, tion. angellyl, methyl vinyl carbinyl, ethyl vinyl car- When an aqueous reaction medium is used the binyl, dimethyl vinyl carbinyl, methyl allyl carhydrazine is conveniently employed in the form binyl, cinnamyl, citronellyl, geranyl, ethyl isoof its dihydrochloride salt, although hydrazine butenyl carbinyl, 2,4-hexadiene-yl-1, and hexhydrate may also be used it desired. Free hydraenyl-l, as well as higher alcohols including oleyl zine can be used when a non-aqueous reaction and linoleyl alcohols, or the unsaturated almedium is employed. Vinyl chloroiormate hycohols derived from China-wood oils or other drolyzes easily and in making the vinyl esters, it drying oils, or the substituted alcohols such as is ordinarily desirable to use a non-aqueous 2-chloroallyl. 2-bromoally1, chlorocrotyl g-chlo- 5 reaction mixture.

Theesters can be recovered from the reaction temperature or lower the desired'ester can be crystallized and filtered from the solvent. Al-

around 70 C., but upon the cooling to room though crystallization is a preferred method for Y recovering the esters, some of the lower boiling members can be recovered by distillation, preferably in vacuo. be effected by dissolving them in a suitable solvent such as isopropyl alcohol or benzene and subjecting the solution while hot to the action of activated charcoal.

The majority of the'esters of the invention are crystalline solids at room temperature 0.), although some of them having highly branched chains will be liquids at this temperature. The esters are very valuable materials in that polymers can be prepared from them having varying properties depending upon the degree of extent of polymerization. If the esters are substantially completely polymerized they form polymers which are infusible and insoluble in all organic solvents, acids and alkalies. Even though such polymers of the esters of the invention contain a nitrogen-to-nitrogen bond therein, the lower members give polymers having remarkable properties of strength and toughness. Furthermore, the compounds polymerize very rapidly and have excellent color stability when exposed to light even though they contain a hydrazo group which usually precludes such property, 1. e. many polymers of amino compounds are subject to rapid discolorationupon exposure to light.

While the esters of the invention can be used as solvents, plasticizers, and softeners for resins and synthetic or natural rubber, the most important use of them is for the production oiv resinous'polymers. The esters are polymerized by the use of heat alone or more preferably by heatin in the presence of a polymerization catalyst. The various oxy en-yielding polymerization catalysts are suitable for this purpose such as benzoyl peroxide, acetyl peroxide, benzoyl acetyl peroxide, lauryl peroxide, dibutvl peroxide, succinyl peroxide, sodium peroxide. barium peroxide, tertiary alkyl hydroperoxides such as tertiary butyl hydroperoxide, peracetic acid, perphthalic acid, nerborates, persulfates. ozone. air and oxygen. The esters can be polymerized also in the presence of their own peroxides or their ozonides. Another class of polymerization catalysts is the di (tertiary alkyl) peroxides, notably di (tertiary butyl) peroxide as described and claimed in the copending application oi Vaughan and Rust, Serial No. 510,420, filed November 15, 1943, which matured as Patent No. 2,403,771 on July 9, 1946. If desired, mixtures of polymerization catalyst can be used, a suitable mixture being that of benzoyl peroxide and ditertiary butyl peroxide as described and claimed in copending application,Serial No. 572,086, filed January 9, 1945, now abandoned. In some cases, it may be desirable to conduct the polymerization in the concurrent presence of both a catalyst and' an inhibitor of polymerization. The amount of catalyst used will ordinarily be between about 0.01% and about 5%, although it is not necessarily limited to this range. In still other cases, it may be desirable to use no other agent to effect Decolorlzation of the esters can polymerization than heat. Polymerization is usually energized by the application of heat although both heat and light may be used together and in some cases light alone is sufllcient. Temperatures'between-about C. and 150 C. are preferred, although higher and lower temperatures can be used. Like other diallyl and related esters, the compounds of the invention polymerize through three successive stages. Upon polymerizing a composition consisting oi the ester, the soluble and fusible form of the polymer is first produced. This first polymer is ordinarily obtained in admixture'with unpolymerized monomeric ester. It can be separated from the monomer by usual procedures and it is characterized by being soluble in many common organic solvents including its monomer. At ordinary atmospheric temperatures this form of the polymer is either a viscous liquid or a soft solid, but it can be rendered flowable by heating. The soluble and fusible polymer is capable of being further polymerized either alone or as it forms in admixture with the monomer. Upon being further polymerized, the -iusible polymer changes to a gel form which is insoluble in the common organic solvents including its monomer. Nevertheless, the insoluble gel is fusible and upon heating is rendered fiowable. Both the soluble polymer and the fusible gel polymer are valuable materials for the usual resin molding operations effected under heat and pressure to form shaped articles because they still further polymerize to the final stage. This final form of the polymer is insoluble in common organic solvents as well as being iniusible. Upon heating the infusible polymer at increasing temperatures, it finally reaches a temperature at which it decomposes, but intermediate between that temperature and room temperature,

it does not become fusible or fiowable although it may -soften slightly so as tobe capable of being bent or curved somewhat without breaking upon application of stress. The esters of the invention are thus seen to be thermosetting, resiniorming compounds and they pass through the three successive stages of polymerization to form first soluble polymer, then insoluble gel polymer and finally iniusible polymer. While the intermediate polymeric forms can be obtained by interrupting the polymerization at a desired stage with separation oi the polymer in the usual manner, the esters can be polymerized through to the final stage without interruption if desired. The interruption of the polymerization of the esters provides valuble materials for further processes. Incomplete polymerization can be used for the production of a syrup comprising a mixture of a monomer and fusible polymer which may be further worked and eventually substantially completely polymerized. The syrup may for instance be transferred to mold of any desired configuration and again subjected to polymerization conditions or it may be used in coating operations or in impregnating bibulous materials, such as paper, fabrics, etc., which in turn may be used in the production of laminates.

The esters of the invention are particularly suited for cast polymerization wherein the monomeric ester is polymerized through to the iniusible polymer in one operation. Cast sheets or rods of the homopolymers are obtained in this manner. When 1% to 5% benzoyl peroxide 4 .is employed, the allyl esters completely polyaeeaeeo It is sometimes desirable to ei'l'ectthe esters. polymerization over a schedule involving varying or increasing temperatures. Excellent results are obtained with the allyl esters by polymerizing with 2% benzoyl peroxide and heating 2 hours at 90 C., then heating at 105 C. for 1 hour, and completing the curing at 115 C. for an additional 3 hours. V

Although particular emphasis has been made in the foregoing description with respect to homopolymers of the esters, the compounds can be mixed with other polymerizable compounds and the mixture subjected to the polymerizing conditions whereby copolymers are produced. Copolymers with modified properties from the homopolymers are obtainable by varying the amount and/or kind of copolymerizable compound mixed with the esters. Any compound capable of addition polymerization is suitable for preparation of the copolymers such as those containing the C Hi=C or vinylidene group like styrene, methyl styrene, butadiene-1,3, isoprene, cyclopcntadiene, vinyl acetate, diallyl phthalate, methyl methacrylate, diallyl diglycolate, allyl acetate, crotyl stearate, ethylacrylate, methyl vinyl ketone, methyl isoparts were obtained indicating a conversion of approximately 98%. The N, N dicarboailyloxy hydrazine was decolorized by dissolving in a boiling aqueous solution of isopropyl alcohol to which activated charcoal was added and filtering while hot, after which the solution was cooled to crystallize the ester. This treatment gave about 76.5 parts 0! white crystals melting at 85 to 86 C. Concentration of the mother liquors yielded about 5 parts more. Analysis of the recrystallized material gave 13.8-and 13.9% nitrogen while the theoretical value is 14.0%.

The N,N' dicarboallyloxy hydrazine was cast polymerized in the presence of 0.5%. of tertiary butyl perbenzoate by heating at 90 C. for 144 hours, whereby a hard, clear infusible and insoluble polymer was obtained. This polymer was subjected to a number of standard tests for resins, the results of which are given in the table below. For purposes of comparison, cast polymerized diallyl phthalate was also tested, this polymer being one or the allyl ester resins having especially good properties. Also for comparison are listed values on another allyl nitrogen-containing ester, namely, dicarboallyloxy ethanolamine. The last two compounds were polymerized in the presence of 2% benzoyl peroxide by heating at 65 C. for 144 hours.

gg ggg- Diearboallyloxy Diallyl Hy dull" Ethenolamine Phthalate Gelation time, bours..... Density. /4 1. ag f i 1 2%; Refractive Index, 20/D 1.5255 1 5189 1 ism Per cent n m transmission at 425 111 originalso 18 I 7'1 After 7 days southern exposure on roof as 74 68 After days southern exposure on roof. 86 68 60 xlggrcol hardness...i 55 43 42 gewise compress on strength, p. s. L. Per cent deformed at ultimahpoint- 22 92 32 Yield point on compression. p. s. i 31 600 20 260 17 000 Per cent deformed at yield point.-. 7,5 e 7 6 4 Flcxural strength, p. s. i. 14 200 16 12 460 Modulus in iicxure. p. s. LX10 6.57 b 43 b Dynstat impact strength. kg. per sq. cm 14 18 26 I A. S. T. M. Method: M93441. 1 A. S. T. M. Method: DWI-MT.

propenyl ketone, acrolein, methacrolein, acrylonitrile, etc. The proportion of copolymerizable compound in admixture with the unsaturated ester of hydrazodicarbonic acid can vary over wide limits as from 1 to 99%. If desired, two or more different copolymerizable compounds can be copolymerized with the ester. In some cases it is desirable to copolymerize two or more different unsaturated esters of hydrazodicarbonic acid.

For the purpose of illustrating one of the methods of preparing the esters of the invention and the properties of a typical member of the class, the following example is given wherein the parts are by weight.

EXAMPLE About 52.5 parts of hydrazine dihydrochloride was dissolved in 300 parts of water. To this solution, which was cooled to 10 to 20 C., was separately added, slowly and simultaneously, a solution of 80 parts of sodium hydroxide in 250 parts of water, and 120.5 parts of allyl chloroformate. After the addition was complete, the reaction mixture was allowed to stand for about 15 hours and the reaction mixture was then warmed nearly to boiling for about 40 minutes, cooled and the precipitated material filtered off.

The precipitate was the crude ester. After air dryin it melted at 74 to 76 C. About 98 The foregoing table shows the ester or the invention gives a polymer having excellent toughness, hardness and strength, as well as unusual stability towards discoloration when exposed to the atmosphere and sunlight.

We claim as our invention:

1. A symmetrical diester of hydrazodicarbonic acid and a monohydric alcohol of 2 to 18 carbon atoms containing an oleflnic linkage.

2. A polymer of the compound defined in claim 1.

zine.

Y 7 e 8 10. A polymer of NiN" dicarbovlnyloxy hydra- UNITED STATES PATENTS zine. I

Number Name Date a ga 2,384,074 Chenicek Sept. 4, 1945 W MCLAMOR 2,385,911 Chenlcek Oct. 2, 1945 2,395,750 Muskat et a1. Feb. 26, 1946 REFERENCES CITED OTHER. REFERENCES- The tollowing references are of recbrd in the Beustem Hami der organ v file of this patent; (2nd Suppl. 4th Ed). pages 78 to 80. 

1. A SYMMETRICAL DIESTER OF HYDRAZODICARBONIC ACID AND A MONOHYDRIC ALCOHOL OF 2 TO 18 CARBON ATOMS CONTAININGS AN OLEFIN LINKAGE. 